A capillary HPLC system typically requires a steel ferrule to connect a capillary to a metal or plastic fluidic port to provide a fluid-tight seal and a substantially zero void volume between the capillary and a conduit embedded within the port. In such a connection, the capillary is held in a fitting having the steel ferrule and a compression nut. The compression nut presses on the ferrule so that the fitting grips the capillary and so the capillary is pressed into direct contact with an inlet or an outlet of the conduit embedded in the port. Once the connection is made, the steel ferrule is permanently secured to the capillary and therefore only usable with a specific port. If the fitting is moved to a different port, even small manufacturing tolerances generally result in either a void volume or an interference which can cause damage and/or cause the steel ferrule to be improperly seated. Moreover, because of the permanent attachment of the steel ferrule to the capillary, if a portion of the fitting is damaged during use, the entire fitting is discarded and a new one installed because any portion of the fitting cannot be simply removed or replaced.
As known in the art, there are alternatives to non-removable, non-reusable and non-replaceable steel ferrules for use in HPLC systems, such as polytetrafluoroethylene ferrules and high performance polyetheretherketone fittings. However, polytetrafluoroethylene ferrules are limited to pressures below a few thousand pounds per square inch (psi), and high performance polyetheretherketone fittings have limited reusability as the polyetheretherketone sealing cone can be damaged from continual use.